Subject: Re: linux-next: build failure after merge of the rcu tree

From: "Paul E. McKenney" <[email-masked]>
Date: Thu, 7 Jan 2016 10:02:44 -0800

On Thu, Jan 07, 2016 at 07:57:25PM +1100, Stephen Rothwell wrote:
> Hi Paul,
> 
> [I found this a few days ago, but I think I forgot to send the email,
> sorry.]
> 
> After merging the rcu tree, today's linux-next build (powerpc
> allyesconfig) failed like this:
> 
> kernel/rcu/rcuperf.o:(.discard+0x0): multiple definition of `__pcpu_unique_srcu_ctl_srcu_array'
> kernel/rcu/rcutorture.o:(.discard+0x0): first defined here
> 
> Caused by commit
> 
>   abcd7ec0808e ("rcutorture: Add RCU grace-period performance tests")
> 
> I have reverted that commit for today.

Hello, Stephen,

Very strange.  The "static" keyword does not mean anything here?
Easy enough to use different symbols in the two different files,
but this situation is not so good for information hiding.

Happy to update rcuperf.c to use a different name, but in the
immortal words of MSDOS, "Are you sure?" :-)

						Thanx, Paul